When a connector is used in an outdoor environment, waterproofing countermeasures are required to prevent direct exposure to rainwater. However, these waterproofing countermeasures increase the complexity of the structure of the connector and the size of the connector. Separate components such as a waterproof case and waterproof seal are required, and these increase costs.
Instead of these waterproofing countermeasures, connectors have been proposed which are able to readily discharge any water that has entered to the outside, thereby reducing the complexity of the structure, the size of the connector, and costs. These connectors reduce corrosion of terminals to the extent that it no longer is a practical problem. (See, for example, Patent Document 1.)
FIG. 15 is a perspective view of a connector of the prior art.
In this drawing, 811 is the connector housing, which has a plurality of terminal accommodating holes 816 and a slit-like metal fitting accommodating recessed portion 817 extending in the transverse direction of the housing 811. A joint terminal metal fitting 851 is inserted into the front of the housing 811. The joint terminal metal fitting 851 has a base portion 853 extending in the transverse direction of the housing 811 and a plurality of terminal portions 852 protruding from the base portion 853. When the base portion 853 is accommodated in the metal fitting accommodating recessed portion 817, each terminal portion 852 is exposed inside the corresponding terminal accommodating hole 816.
The terminal accommodating holes 816 pass through the housing 811 in the longitudinal direction, and electrical wire terminals connected to the leading ends of electrical wires not shown in the drawing are inserted on the side opposite the inserted joint terminal metal fitting 851. The electrical wire terminals of the electrical wires inserted into each terminal accommodating hole 816 come into contact with the corresponding terminal portion 852, and an electrical connection is established with a plurality of electrical wires.
A flange-like annular rib 844 is formed on the outer periphery of the housing 811 near the front end, and a cap 841 is connected to the annular rib 844 via a flexible connecting piece 845. After the base portion 853 of the joint terminal metal fitting 851 has been accommodated inside the metal fitting accommodating recessed portion 817, the cap 841 is displaced so as to cover the front surface of the housing 811. In this way, the front end of the housing 811 is accommodated inside the interior space 842 of the cap 841 while the outer periphery is covered. As a result, water does not enter the terminal accommodating holes 816 from the front of the housing 811 even when exposed to rainwater.
Because the rear end of the housing 811 is not covered, water can enter the terminal accommodating holes 816 from the rear via the gaps between the electrical wires. However, a through-hole 843 connecting the interior space 842 to the outside is formed on the bottom side of the cap 841 when covering the front end portion of the housing 811. Therefore, any water entering the terminal accommodating holes 816 does not pool inside the terminal accommodating holes 816 but is discharged to the outside via the through-hole 843. As a result, the electrical wires and the joint terminal metal fitting 851 do not become corroded.    Patent Document 1: Laid-Open Patent Publication No. 2014-232584